1. Field of the Invention
This invention relates to a communication terminal apparatus in a radio communication system such as, for example, a mobile telephone system.
2. Description of the Related Art
In the wideband code division multiple access (W-CDMA) system that is one of the mobile telephone systems, generation of an incoming call is monitored in the intermittent reception scheme.
In the intermittent reception scheme, a communication function is performed in a period in which a paging signal is transmitted intermittently from a base station to notify presence of an incoming call (ready state). An operating unit, a display unit and their related sections are operated in the other period (sleep state).
If it is detected that there is an incoming call from the paging signal in the ready state, intermittent reception is stopped and the communication function is continuously performed to make communication. If no incoming call from the paging signal is detected, a timer is reset, and a power supply of each unit is turned OFF such that the unit becomes in the sleep state again by the time when the paging signal is transmitted.
Thus, consumed power can be reduced by employing the intermittent reception scheme at the incoming call standby time.
However, it is requested to further enhance the effect obtained by the intermittent reception scheme, reduce the consumed power and extend the standby time.